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  • This session has been presented June 20, 2014.

Description

  • Speaker

    Tancrède Lepoint - CryptoExperts

Le chiffrement complètement homomorphe (parfois considéré comme le Saint Graal de la cryptographie) permet d'effectuer (de façon publique) des calculs arbitraires sur des messages chiffrés. Les premières instanciations de cette surprenante primitive ne peuvent être considérées comme pratiques, chaque multiplication de deux bits chiffrés nécessitant d'être suivie par une procédure de plusieurs dizaines de minutes.<br/> Dans cet exposé, nous présentons le chiffrement homomorphe et discutons sa praticité et ses limitations. Il existe plusieurs grandes familles de chiffrement homomorphes, mais les familles basées sur RLWE et les entiers semblent les plus prometteuses. Nous parlerons aussi de l'envoi de données vers le Nuage (le cloud), qui pose actuellement de nombreux problèmes du fait de la grande taille des chiffrés comparée à la taille des messages en clair.

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